This invention relates to the production of partially fried, frozen potato strips, which when finish fried provide french fries having improved textural characteristics. More particularly, the invention relates to a process for producing frozen par-fried potatoes which remain crisp and rigid for extended periods of time after finish frying.
A sizeable market has developed in recent years in the institutional food trade such as restaurants, fast food stores and the like, for frozen, partially fried potato strips which require only a brief period of further cooking before serving. Such potato products, which are generally referred to as par-fries, are produced by peeling, cutting and trimming raw potatoes into strips of a suitable size, which are blanched in steam or hot water to partially cook the potatoes. The blanched strips are then partially fried (par-fried) in hot fat or oil and are frozen. Such frozen par-fries are prepared for consumption by finish frying in deep fat or oil for a short period of time, usually about 1-3 minutes. The use of such frozen par fry potato strips offers convenience and savings in labor costs, since they need only be removed from the package and finish fried for a short time, thereby eliminating the necessity for washing the potato, peeling, cutting it into strips and frying for extended periods of time, as is required when french fries are prepared from raw potatoes. However, par fried potato strips available heretofor commonly suffer from the disadvantage that when prepared for consumption they are unstable as to texture. Thus, immediately after finish frying, the potato strips have a desirable crisp texture, but become limp and soggy within a few minutes after preparation. Such limpness of the french fries results in objectionable appearance, taste and texture and is a primary feature by which consumers identify a poor product.
A number of solutions have been proposed in order to improve the crispness and rigidity of par-fried potatoes after finish frying. For example, the surface treatment of potato strips with firming agents such as modified starches, gums, alginates, calcium salts, and the like has been suggested to improve the crispness of the strips after finish frying. The results obtained by such surface treatment procedures, however, have been successful to only a limited degree and vary with the condition of the raw potatoes used. As a result, control of surface crispness and rigidity of the finished fries is largely dependent upon the quality of the raw potato, which varies throughout the year, and may be seriously affected during the production of the par-fried potato strips. U.S. Pat. No. 3,397,993 discloses a process for producing frozen par fried potato strips in which the strips are first blanched to a translucent condition and are then dried in hot air (150.degree.-350.degree. F.) to remove between 20%-30% moisture prior to par frying and freezing. U.S. Pat. No. 3,649,305 discloses a process in which potato strips are dried in hot air (150.degree.-350.degree. F.) to remove between 10%-30% moisture, after which the strips are blanched, par fried and frozen.
The present invention provides a process for the production of par-fried potato strips which have a crisp surface layer and a mealy inner core after finish frying and which retain their surface crispness and rigidity for an extended period of time after finish frying. In addition the present process provides a significant savings in the amount of energy required to produce the product, as compared to prior art procedures which involve drying of the potato strips in hot air prior to par frying.